Horizontal pump



Aug. 10 1926'l Patented Aug. 10, 1,925 i,

UNITED STATES 1,595,636 PATENT oFF-TCE.

MICHAEL E. WALTEIRS AND ARTHUR R. W-EIS, 0F HUNTINGTON PARK, CALIFORNIA,

ASSIGNORS TO PACIFIC PUMP WORKS, 0F

CORPORATION OF CALIFORNIA.

`HUNTINGTON PARK, CALIFORNIA, A

HORIZONTAL PUMP. i

Application mea January 13,1925.' serial No. 2,153.

This invention relates to horizontal centrifugal pumps, and it relatesparticularly to two-stage pumps of this type.

' FThe present form of two' stage centrifugal pump generally has a firststage impeller chamber and a second stage impeller chamber, in whichfirst stalge and second stage impellers are respectively positioned,these im,- pellers being secured to a shaft which is adapted for drivingthrough suitable means. A suction passage connects with aconcentricentrance of the first stage impeller. A fluid such as water enters thesuction passage and .flows into the impeller entrance. The fluid isengaged by blades of the first stage im.- peller and is thrown to theperiphery of the impeller due to centrifugal force. The Huid leaves theperiphery of the first stage impeller, passing into the first stageimpeller chamber and from thence it Hows into' .a crossover passagewhich connects between the peripheryof the first stage impeller chamberand a concentric mouth of the second stage impeller chamber.VVaterenters the mouth of the second stage impeller and is rotated byblades thereof, the water being thrown outward by centrifugal force. Theaxial pressure of the water against the impellers of the pum-p tend tomove these. vimpellers axially along the shaft` on which theyrarecarried, and it is, therefore, neces,- 'sary to provide means forsecuring them against axial movement, such means as lock nuts beingcustomary arrangements employed .for this purpose. The cross overpassage connecting between lthe first and secondl stage impellerchambers is generally provided in an eXtra casting which is bolted tothe main body of the pump.

It is anobject of our invention to provide a horizontal centrifugal pumpof the type mentioned-in which the pressure against the impellersthereof is substantially in equilibrium. We accomplish'this bv providingfirst and second stage impellers which are in the form of an integralrotor. 'Water from an inlet passage of the pump enters the first stageimpeller, and water from a cross over of the pump enters the secondstage impeller in such a manner that thewater pressure opposing axialmovement in the integral rotor is counteracted., This particularconstruction tends to neutralize the tendency of movement in .therotor.' The centrifugal pump is constructed., however, so that therewill be a slight leakage between the impelf to remain in a properpositionagainst an.

abutment so located thatl the impellers will be `properly positioned intheir impeller chambers and so that the rotor will not engage the bodyof the pump.

It is another object of our invention to provide a centrifugal pump ofthis character in which the cross over passage which 'extends betweenthe first and second stage' impeller chambers is formed in the main bodyof the pump. This eliminates an eXtrav casting as was previouslynecessary. It reduces the cost of the pump, makes the'pump more compact,and renders it of a better design.

, Other objects and advantagesb of this invention will appear in thefollowing specification.

With reference to the two sheets of drawl ings which are forillustrative purposes onlv,

. Fig. 1 is a vertical longitudinal cross section of a two-stagehorizontal centrifugal pump taken substantially on the line 1-1 of Fig.2.

Fig. 2 is an end View of the pump shown in Fig. 1 taken as indicated bythe arrow 2 of Fig. 1.`

Fig. 3 is va vertical cross section taken l through a first stageimpeller chamber of the pump, this section being taken substantially onthe line 3 3 of Fig. 1.v

` Fig. 4 vis a vertical cross section taken through a second stageimpr-ller chamber of theY pump, this view beingtaken substan tially onthe line 4 4 of Fig. 1. y

The form of our invention shown in the drawings provides a base 11 and acap 12 which cooperate to provide a main body 13. yThese members 11 and12 are provided with flanges 15 and 16, respectively, throughL whichbolts 17 ext-end 'in a manner to secure these members together. Afirst/stage impeller chamber '18,and a second stage impeller chamber 19are provided in the body eoA sides of the chambers 18 and 19. An arm.

27 at the left side of the .body 13 carries a bearing box 28, in whichball bearings 29 supporting the left end of the shaft 23 is secured. Anarm 31 provided at the right end of the body 13 carries a bearing box 32which supports a bearing 33, this bearing 33' rotatably support-ing theright end of the shaft 23. This construction is substantially the sameas the bearin construction at the left hand end of the ody 13. The righthand end of the shaft 23 extends entirely through the box 32 as shown,and has a fiexible connection flange 34 secured at the end thereof,thereby providing a means through which the shaft 23 may ber driven.

A rotor 36 is carried by the shaft 23; `this rotor has a hub portion 37which surrounds the shaft 23 and which is secured thereto i by means ofa gib head key 38 having a gib head 38EL forming an abutment againstwhich the leftward end'of the hub 37 engages.

This hub 37 extends through the opening 21 in the central Wall 20 andextends into the chambers 18 and 19. A first stage impeller 39 is`formed integral with the hub 37 and is positioned in thefirst stageimpeller chamber 18, and a second stage irnpeller 4() isformed integralwith the hub 38 and is positioned in the second stage impeller chamber19 as shown clearly in, Fig. 1 of the drawings. rThe first stageimpeller is rovided in the .form of a radial wall 42 which extends fromthe hub 37; a plurality of blades 43; and a radial Wall 44, the radialWall r44 being spaced away from the wall 42 bythe plurality of blades43. An annular projection 45 extends concentrically from the radial wall44 into a suction mouth 46 of the body 13.

The second stage limpeller 40 includes a radial IWall 48 .which extendsfrom the hub 37 ,Y and a radial `wall 49. The radial wall y49 is spacedaway from the radial wall 48 by means of a plurality of bladesI 50. Anannular projection 51 extends concentrically from the radial wall 49into a `cross over mouth 53 of the body 13. The annular projection 45provides a concentric entrance 54 for the first stage impeller 39 withthe suction mouth 46 of the body 13.

A cross over passage 60 is formed in the body 13.

chamber 18 and the concentric cross over mouth 53 of the body 13. As isevident from the drawings, this cross over passage 60 extends from thefirst stage impeller chamber 18 around the second stage impeller chamber19 to the cross over mouth 53. An exhaust passage 63 connects with theperiphery of the second stage impeller cha-n1- ber 19 as clearly shownin Fig. 4 of the drawings. v

Water or any other fluid enters the suction passage 58 through suitablemeans such as piping 64 whichis connected to the body 13 as shown inFig. 2. This water passes through the suction passage 58 and enters theconcentric entrance 54 of the first stage impeller 39. The shaft 23 androtor 38 at this time are rotatetd at a high rate of speed. By reasonof' engagement of the water by the blades 43, the water is givenrotation. Centrifugal force, due to this rotation, throws the wateroutward through the impeller 48 at a high velocity into the periphery ofthe first stage impeller chamber 18. The water passes from the peripheryof the first stage impeller chamber 18 into the cross over passage 60.From the cross over passage' 60, the water passes into the concentricentrance 55 of the second stage impeller 40. The water is engaged byblades 50 of this impeller and is caused to rotate. Centrifugal forcethrowsthe Water outward from the impeller at a high velocity into thesecond stage impeller chamber 19. The water Hows around the periphery ofthe This cross over passage 60 as 1 shown in Figs. 1, 3 and4 connectsbetween the periphery of they first stage impeller second stage impellerchamber 19, and passes therefrom into the exhaust passage 63 and iscarried therefrom by Suitable means such as a pipe 66 which isconnectedto the body 13 as shown in Fig. 4 of the drawings.

By inspection of Fig." l it is evident that the Water entrances 54 and55of the first and second stage impellers 39 and 40 are extended inopposite or opposing direc; tions. It is likewise evident that waterentering these entrances 54 and 55 passes thereinto in opposingdirections. vTater pressure in the first stage impeller cham-` ber 18.produces a tendency for the first stageimpeller 39' to move in aleftward direction, and the Water pressure in the v second stageimpeller 19 produces a tendency forthe second stage impeller 40 to movein a rightward direction; that is, the tendency for the impellers 39 and4() is to moveI in opposite directions. 2l in the central Wall 2O` ismade slightly larger than that portion of the hub 37 which extendstherethrough. This is The opening tentionally provided thusly so thatthere ,w1ll be a slight leakage from the high pressure chamber 192intothe low pressure chamber 18. If there were no leakage be? tween thesechambers, the tendency of movement of the impellers 39 and 40 inopposite directions would be equalized, this being due to the well knownthrust ratio for opposed double stage. centrifugal pumps of this generaltype, in which the discharge pressure of the first stage less the.intake pressure thereof denotes thrust-towards the intake end of thepump and in which the discharge pressure of the second stage less theintake pressure thereof denotes thrust in the opposite direction. If thepump herein illustrated were not provided with interchamber leaka e thethrust e nation would be P18-P54: -1355, in w ich P denotes pressure,and in which the numerals are reference characters in Fig. 1 and used inthe equation to designate the respective intakes and discharge .portionsof the two stages. However, as it is not desired to have the rotor inequilibrium, the interchamber leakage is provided to lower P19, therebydecreasing the 'right thrust'of the high, pressure stagev and toincrease P18, thereby increasingfthe left thrust of the low pressurestage, with a resulting predominant left thrust for the complete pump.There is then a very slight tendency for the rotor' 36 to move in aleftward direction. The leftward end. of the hub 37 as previouslymentioned, engages the gib head 38a of the key 38 which prevents amovement of the rotor 36; however, when the rotoris being rotated, therotor y36 Valwayspressurably engages with the gib head.38. This isextremely desirable owing to the .fact that it retains the rotor 36 in aproper`working position.

is retained in the position shown 1n ther The rotor drawings so that theimpellers arecentralized in their impeller chambers and so that therotor is not engaged with the body 11 of the pump at any point. If therotor were exactly in equilibrium, there would be a freedom 'thereofrelative to the shaft, and the rotor would remain not in a certainposition, but in any position into which it is forced during thestarting of the pump. The rotor might at .this time engage with thebody. of the pump, causing in my invention. The shaft 23 is reversibleand makes the pump convertible from a right hand drive into a-left handdrive.

pump. This is possible because .of the fact that the shaft is uniformlycylindrical, and there are no formations which would interfere if theshaft 23 were reversed.

It is -a feature of the invention to provide a novel arrangementwhichincludes the cross over passage 63. Our invention is so designed that itis possible for us to form the cross over passage in Ithe main body 13of the pump. We accomplish this by reason of the compactness of designof our invention. By being able to form the cross over passage 60 withinthebody 13, it is possible for us to produce an "eiicient pump at acheaper cost than pumps of this type which require an extra castingwhich is bolted to the main casting for the cross over` of the pump. Theelimination of anl extra casting also contributes to superiority indesign, making a pump which is of better appearance and more compactthan othv er pumps. l

Although we have described and delineated our invention in the form of atwostage centrifugal pump, we wish' it to be clearly understood that wemay employ our invention in pumps having more 4stages and other designswithout departing ,from thespirit and scope of this invention. V Veclaim as our invention: p 1. In a centrifugal pump, the combina-- tionoff: a housing forming a first stage im- 'peller chamber and an adjacentsecond stage impeller chamber; a drive shaft extendine' through saidchambers; a rotor carried by andV slidable on said shaft, said rotorcomprising first andsecond stage impellers positioned respectively insaid first and second stage chambers; and a key rotatably connectmg saidrotor to said shaft and formed to' provide an abutment limiting thelslidingof the rotor on the shaft in oneY direction.

2./In ra centrifugal pump, the combination of z' a housing forming afirst stage impeller chamber and Aan adjacent second 'stage' impellerchamber separated by a wall having an axial opening; a drive shaftextending through said ,chambers and sald opening; a rotorcarried by andslidable on said shaft, said rotor comprising a. hub surrounding theshaft and extending through said opening and irst'and second stageimpellersl extending from said hub into the res pectivev chambers; and akey rotatably connecting said rotor vto said shaft and formed to providean abutment to be en.

gaged by one end of said hub to limit-the sliding of the rotor on thevShaft in one direction.

3. In a centrifugal pump, the combina-y tion of: a housing forming a lowpressure impeller chamber having a suction inlet, a high pressureimpeller chamber having a discharge outlet, a cross-over passageconnecting the low pressure chamber outlet with the high pressurechamber inlet, and a wall separating said chambersand having an axialopening; a drive shaft extending through said chambers and said axialopening; a rotor carried by and slidable on said shaft, said rotorcomprising a hub surrounding the shaft and 'extending through saidopening and low and high pressure impellers extending from said hub intothe respective chambers; and a key rotatably connecting said rotor tothe shaft and formed to provide an abutment to be engaged by one end ofsaid hub to limit the sliding of the rotor on the shaft in onedirection, said opening being of a diameter larger than said hub topermit constant leakage from the high to thelow pressure chambers toinsure an axial thrust suiiicient to maintain the rotor hub inengagement with said abutment.

4. In a centrifugal pump.` the combination 0f: walls forming an impellerchanber having an inlet and `an outlet passage; a shaft extendingconcentrically through said impeller chamber; a rotor carried by saidshaft in said impeller chamber; and a key rotatabl connecting said rotorwith said shaft an having a head forming a stop, said rotor beingslidable on said shaft Iand held against said head `of said key by v,thepressure of a fluid passing into said impeller chamber through saidinlet passage.

5'. In a centrifugal pump, the combination of a housing forming a lowpressure chamber and an adjacent high pressure chamber; a drive shaftextending through said chambers; lopposed! impellers carried by and indriving relation with said shaft, one of said impellers being positionedin each chamber; and means providing leakage from said high pressurechamber to said low pressure chamber to at all times insure apredominant axialA thrust of the impellers towards the low pressurecham-- ber.

6. In a tion of: a housing forming a low pressure chamber and anadjacent high pressure chamber; a drive shaft 'extending through saidchambers and provided with an abut ment; impellers slidable on saidshaft and rotatable therewith, one of said impellers being positioned 1neach chamber; and

centrifugal pump, the combina-` means providing interchamber leakageinsuring a predominant axial thrust ofthe impellers towards saidabutment.

7. In a centrifugal pump, the combinai ment; and an impeller slidable onsaid shaft and rotatable therewith and positioned within said chamber,said impeller 4 being adapted to exert an axial thrust maintaining it inengagement with said abutment.

`8. ln a centrifugal pump, the combination of: a housing forminga lowpressure chamber and an adjacent high pressure chamber; a drive shaftextending through said chambers; and opposed propellers carried by andin driving relation with said shaft, one of said impellers being,positioned in each chamber and the housing being formed to provideleakage from` said high pressure chamber to said` low pressure chamberto at all times -insure a predominant axial thrust of the impellersvtowards the low pressure chamber. f i E 9. In a centrifugal pump, thecombinau tion of: a housing forming a low pressure chamber and anadjacent high pressure chamber; a drive shaft extending through saidchambers and provided with an abutment; and impellers slidable on saidshaft.

and rotatable therewith, one of said impellers'being positioned in eachchamber and the housing being formed to provide interchamber leakageinsurin nant axial thrust of the impe ers towards said abutment. y

10. Ina multi-stage centrifugal pump of the opposed impeller type, thecombination of: a housing forming a low pressure cham- MICHAEL E.wALTERs. ARTHUR R. wEis.

a predomi-

